48 The Endocrine Organs 



confirmed by Noel Paton, who finds that the converse is also true, viz., that 

 castration in the guinea-pig is followed by increase in size of the thymus. 

 In castrated cattle also the thymus is nearly double the size that obtains 

 in uncastrated beasts (J. Henderson). In all castrated animals the involu- 

 tion of the gland is retarded. 



Noel Paton has also found that removal of both thymus and testicles 

 has a marked effect in delaying the rate of growth of guinea-pigs, whilst 

 this result is not obtained by removal of thymus or testicles alone. 



In the female no such relationship has been established between the 

 generative glands and the thymus. 



